1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 24 */ 25 /* 26 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 #pragma weak llrintl = __llrintl 31 #if defined(__sparcv9) || defined(__amd64) 32 #pragma weak lrintl = __llrintl 33 #pragma weak __lrintl = __llrintl 34 #endif 35 36 #include "libm.h" 37 38 #if defined(__sparc) 39 40 #include "fma.h" 41 #include "fenv_inlines.h" 42 43 long long 44 llrintl(long double x) { 45 union { 46 unsigned i[4]; 47 long double q; 48 } xx; 49 union { 50 unsigned i[2]; 51 long long l; 52 } zz; 53 union { 54 unsigned i; 55 float f; 56 } tt; 57 unsigned int hx, sx, frac, fsr; 58 int rm, j; 59 volatile float dummy; 60 61 xx.q = x; 62 sx = xx.i[0] & 0x80000000; 63 hx = xx.i[0] & ~0x80000000; 64 65 /* handle trivial cases */ 66 if (hx > 0x403e0000) { /* |x| > 2^63 + ... or x is nan */ 67 /* convert an out-of-range float */ 68 tt.i = sx | 0x7f000000; 69 return ((long long) tt.f); 70 } else if ((hx | xx.i[1] | xx.i[2] | xx.i[3]) == 0) /* x is zero */ 71 return (0LL); 72 73 /* get the rounding mode */ 74 __fenv_getfsr32(&fsr); 75 rm = fsr >> 30; 76 77 /* flip the sense of directed roundings if x is negative */ 78 if (sx) 79 rm ^= rm >> 1; 80 81 /* handle |x| < 1 */ 82 if (hx < 0x3fff0000) { 83 dummy = 1.0e30f; /* x is nonzero, so raise inexact */ 84 dummy += 1.0e-30f; 85 if (rm == FSR_RP || (rm == FSR_RN && (hx >= 0x3ffe0000 && 86 ((hx & 0xffff) | xx.i[1] | xx.i[2] | xx.i[3])))) 87 return (sx ? -1LL : 1LL); 88 return (0LL); 89 } 90 91 /* extract the integer and fractional parts of x */ 92 j = 0x406f - (hx >> 16); 93 xx.i[0] = 0x10000 | (xx.i[0] & 0xffff); 94 if (j >= 96) { 95 zz.i[0] = 0; 96 zz.i[1] = xx.i[0] >> (j - 96); 97 frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96)); 98 if (((xx.i[1] << 1) << (127 - j)) | xx.i[2] | xx.i[3]) 99 frac |= 1; 100 } else if (j >= 64) { 101 zz.i[0] = xx.i[0] >> (j - 64); 102 zz.i[1] = ((xx.i[0] << 1) << (95 - j)) | (xx.i[1] >> (j - 64)); 103 frac = ((xx.i[1] << 1) << (95 - j)) | (xx.i[2] >> (j - 64)); 104 if (((xx.i[2] << 1) << (95 - j)) | xx.i[3]) 105 frac |= 1; 106 } else { 107 zz.i[0] = ((xx.i[0] << 1) << (63 - j)) | (xx.i[1] >> (j - 32)); 108 zz.i[1] = ((xx.i[1] << 1) << (63 - j)) | (xx.i[2] >> (j - 32)); 109 frac = ((xx.i[2] << 1) << (63 - j)) | (xx.i[3] >> (j - 32)); 110 if ((xx.i[3] << 1) << (63 - j)) 111 frac |= 1; 112 } 113 114 /* round */ 115 if (frac && (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u || 116 (frac == 0x80000000 && (zz.i[1] & 1)))))) { 117 if (++zz.i[1] == 0) 118 zz.i[0]++; 119 } 120 121 /* check for result out of range (note that z is |x| at this point) */ 122 if (zz.i[0] > 0x80000000u || (zz.i[0] == 0x80000000 && (zz.i[1] || 123 !sx))) { 124 tt.i = sx | 0x7f000000; 125 return ((long long) tt.f); 126 } 127 128 /* raise inexact if need be */ 129 if (frac) { 130 dummy = 1.0e30F; 131 dummy += 1.0e-30F; 132 } 133 134 /* negate result if need be */ 135 if (sx) { 136 zz.i[0] = ~zz.i[0]; 137 zz.i[1] = -zz.i[1]; 138 if (zz.i[1] == 0) 139 zz.i[0]++; 140 } 141 return (zz.l); 142 } 143 #elif defined(__x86) 144 long long 145 llrintl(long double x) { 146 /* 147 * Note: The following code works on x86 (in the default rounding 148 * precision mode), but one ought to just use the fistpll instruction 149 * instead. 150 */ 151 union { 152 unsigned i[3]; 153 long double e; 154 } xx, yy; 155 int ex; 156 157 xx.e = x; 158 ex = xx.i[2] & 0x7fff; 159 160 if (ex < 0x403e) { /* |x| < 2^63 */ 161 /* add and subtract a power of two to round x to an integer */ 162 yy.i[2] = (xx.i[2] & 0x8000) | 0x403e; 163 yy.i[1] = 0x80000000; 164 yy.i[0] = 0; 165 x = (x + yy.e) - yy.e; 166 } 167 168 /* now x is nan, inf, or integral */ 169 return ((long long) x); 170 } 171 #else 172 #error Unknown architecture 173 #endif 174